【摘要】 利用微生物分离培养方法从互花米草根部和叶片获得内生细菌,经重金属筛选,分离到一种耐受重金属Cu2+、Pb2+和Cr6+的细菌.为了进一步鉴定分离菌株,利用PCR方法扩增其部分16SrDNA序列,目标DNA条带约1 500bp,测序和在线分析结果后显示,所测序列均与基因库中已上传的Lysinibacillus sphaericus菌株16SrDNA序列(KJ878614.1,JN613478.1)相似性均为100%.初步鉴定该菌为Lysinibacillus属球形芽孢杆菌(Lysinibacillus sphaericus),命名为Lysinibacillus sphaericus QZ1-1.对该菌株采用促生长特性分析结果显示,该菌株具有产生IAA和ACC的能力,同时该菌能在无氮培养基中生长,具备固氮功能,为日后重金属污染生物修复相关研究提供了良好的目标菌株.更多还原

【Abstract】 Endophytic bacteria were obtained from roots and leaves of Spartina alterniflora using culture-dependent method.After heavy metal screening,a strain showed resistance to Cu2+,Pb2+and Cr6+was obtained.To further characterize the isolation,partial 16 SrDNA with length 1 500 bp was amplificated and sequenced.Online analysis suggested that all sequences showed 100%sequence identity to previously submitted strains Lysinibacillus sp.ES3-1(KJ 878614.1)and Lysinibacillus sp.OE16(JN 613478.1).We infered the isolation belongs to Lysinibacillus sphaericus,named Lysinibacillus sphaericus QZ1-1.Growth characteristic analysis indicated that this strain could produce IAA and ACC deaminase,grow in nitrogen-free medium,suggesting its ability of nitrogen fixation.This study indicated that Lysinibacillus sphaericus QZ1-1is a strong candidate for further related studies because of its potential phytoremodiation of heavy metal pollution.更多还原